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libavcodec
h261.c
Go to the documentation of this file.
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/*
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* H.261 common code
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* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
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* Copyright (c) 2004 Maarten Daniels
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* H.261 codec
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*/
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#include "
avcodec.h
"
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#include "
h261.h
"
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#define IS_FIL(a) ((a) & MB_TYPE_H261_FIL)
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static
void
h261_loop_filter
(
uint8_t
*
src
,
int
stride
)
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{
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int
x, y, xy, yz;
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int
temp
[64];
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for
(x = 0; x < 8; x++) {
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temp[x] = 4 * src[x];
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temp[x + 7 * 8] = 4 * src[x + 7 *
stride
];
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}
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for
(y = 1; y < 7; y++) {
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for
(x = 0; x < 8; x++) {
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xy = y * stride + x;
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yz = y * 8 + x;
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temp[yz] = src[xy -
stride
] + 2 * src[xy] + src[xy +
stride
];
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}
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}
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for
(y = 0; y < 8; y++) {
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src[y *
stride
] = (temp[y * 8] + 2) >> 2;
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src[y * stride + 7] = (temp[y * 8 + 7] + 2) >> 2;
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for
(x = 1; x < 7; x++) {
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xy = y * stride + x;
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yz = y * 8 + x;
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src[xy] = (temp[yz - 1] + 2 * temp[yz] + temp[yz + 1] + 8) >> 4;
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}
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}
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}
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void
ff_h261_loop_filter
(
MpegEncContext
*
s
)
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{
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H261Context
*
h
= (
H261Context
*)s;
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const
int
linesize = s->
linesize
;
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const
int
uvlinesize = s->
uvlinesize
;
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uint8_t
*dest_y = s->
dest
[0];
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uint8_t
*dest_cb = s->
dest
[1];
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uint8_t
*dest_cr = s->
dest
[2];
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if
(!(
IS_FIL
(h->
mtype
)))
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return
;
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h261_loop_filter
(dest_y, linesize);
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h261_loop_filter
(dest_y + 8, linesize);
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h261_loop_filter
(dest_y + 8 * linesize, linesize);
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h261_loop_filter
(dest_y + 8 * linesize + 8, linesize);
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h261_loop_filter
(dest_cb, uvlinesize);
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h261_loop_filter
(dest_cr, uvlinesize);
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}
h
h
Definition:
vp9dsp_template.c:2038
temp
else temp
Definition:
vf_mcdeint.c:256
H261Context
H261Context.
Definition:
h261.h:37
uint8_t
uint8_t
Definition:
audio_convert.c:194
src
#define src
Definition:
vp8dsp.c:255
H261Context::mtype
int mtype
Definition:
h261.h:42
s
#define s(width, name)
Definition:
cbs_vp9.c:257
avcodec.h
Libavcodec external API header.
MpegEncContext::linesize
ptrdiff_t linesize
line size, in bytes, may be different from width
Definition:
mpegvideo.h:134
h261.h
H.261 codec.
MpegEncContext::uvlinesize
ptrdiff_t uvlinesize
line size, for chroma in bytes, may be different from width
Definition:
mpegvideo.h:135
IS_FIL
#define IS_FIL(a)
Definition:
h261.c:31
MpegEncContext
MpegEncContext.
Definition:
mpegvideo.h:81
stride
GLint GLenum GLboolean GLsizei stride
Definition:
opengl_enc.c:104
MpegEncContext::dest
uint8_t * dest[3]
Definition:
mpegvideo.h:295
h261_loop_filter
static void h261_loop_filter(uint8_t *src, int stride)
Definition:
h261.c:33
ff_h261_loop_filter
void ff_h261_loop_filter(MpegEncContext *s)
Definition:
h261.c:61
stride
#define stride
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